The Coastal Environment
AQA B Geography
Revision Guide
Case Study: How is the Holderness Coast an example of a multi-use
area?
Definition: A multi use area is a part of the
coastline which offers a range of social, economic
and environmental activities.
Flamborough Head – stunning scenery and
birds attracts tourists to visit.
Bridlington – provides retirement homes with
sea side views.
Hull – Every year, 13 million tonnes of
imported cargo pass through the port which
employs 5000 people. Fishing industry lands
fish at Hull docks.
Holderness Country Park – provides tourists
with a large fishing lake and a dog walking
area. Guests can stay in either log cabins or
caravans.
Easington Gas Terminal – provides 1000 jobs
and 25% of UKs gas supply.
Humber Estuary: off-shore & on-shore wind
turbines use strong winds to generate renewable
electricity.
Case Study: Why has the Holderness Coastline developed?
Human Activities
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Improved Transport
Rising living standards
Range of jobs (e.g. Easington for
industry, Bridlington for tourism).
Tourism (scenery and wildlife) (e.g
Flamborough Head and Spurn Head)
Attractive place to live (e.g.
Bridlington – views of the sea)
Second homes/retirement (e.g.
Bridlington)
Economic Activities
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Improved Transport and
Communication
Available space (e.g. Hull for
development of industry and
housing)
Large workforce (e.g. Hull which
employs 5000 people in its dockland)
Natural Resources (e.g. fish in Hull,
gas in North Sea piped to Easington)
Tourism (e.g. Hornsea, Bridlington,
Various caravan and camping sites
along the coastline)
How is development impacting the environment?
Some animals and
birds have choked
on litter on beaches
from tourists.
Conflicts of Interest :
Different coastal users who
make problems for each
other.
•Oil refineries of S. Humber
pollute water for local
fishermen.
Coral reefs (e.g. St Lucia)
are being damaged from
tourists collecting souvenirs
and anchors from fishing
vessels.
How is development
along the coast
damaging the local
environment?
Footpath erosion at
Flamborough Head due
to high tourist numbers.
•Ships coming up R. Humber
cause danger for tourist
wind-surfers & jet skiers
•Wind turbines at Easington
can kill migrating birds using
Spurn for migration.
Industrial units and
factories have polluted the
sea causing death of
aquatic life and thus
disrupting food chains.
Diesel/oil spillage
from the tankers may
affect marine life;
noise from tankers
Cliff top developments
have made the cliffs
unstable which has
increased rates of erosion.
Sea defences along the Holderness
Coastline have stopped the
movement of sediment to Spurn
Head, an important habitat for
numerous rare birds .
Case Study: How is the Holderness Coastline protected?
Protection Scheme
How does it protect the coastline?
Heritage Coast at
Flamborough Head
-Encourages the use of public transport which reduces cars, congestion, noise and
air pollution
- farmers receive extra money through grants if they farm in a way that protects
the environment and wildlife biodiversity (range of species)
- footpath erosion is reduced by encouraging people to stay on paths through
signage
Yorkshire Wildlife
Trust at Spurn and
Flamborough Head
-Organises seasonal beach cleans at two locations. All rubbish is separated out and
recycled where possible which promotes sustainability
-Helps to prevent millions of marine animals, birds, turtles and fish dying each year
as a result of entanglement or eating litter floating around in the sea or beach.
-Keeps beaches tidy which encourages tourists back into the area.
Greenbelts around
Bridlington and
Hull
-they have prevented new houses and industries from being built land ideal for
farming land.
-fewer development on cliff-faces has reduced the pressure on cliffs making them
more resistant to erosion and weathering.
-stopped woodlands and hedges being removed allowing for ecosystems to
continue to flourish.
Marine
Conservation Sites
(MCS)
-The MCS has helped reduced overfishing to protect fish stock numbers from
further declining. In the future, it is hoped that fish populations will increase.
-The MCS also prevents sand dredging of the sea bed which can damage nesting
sites of many fish.
What are the differences between constructive and destructive waves?
What determines the strength of a wave?
Swash is the
movement of
water up the
beach
Backwash in
the movement
of water down a
beach
-
Strength of the wind
How long the wind has been blowing
The distance between the ocean the wave has
crossed (fetch)
Constructive Waves
Destructive Waves
Strong Swash, Weak Backwash
Weak Swash, Strong Backwash
Deposits rather than erode
Erodes rather than deposits
Low wave height (less than 1 metre)
High wave height (more than 1 metre)
Low wave frequency
High wave frequency.
What are the types of erosion and weathering?
Key Terms:
Erosion – the wearing away of rocks by the action of the sea and their removal
Weathering – the breaking up of rocks in situ by the action of the weather, chemicals and
biology.
Erosion
Attrition
Energy from breaking waves causes rocks and
pebbles to smash into each other They
eventually break down into smaller and
rounder pieces
Abrasion
Materials, like boulders, pebbles and sand are
hurled against the cliff by breaking waves.
This causes undercutting and the breaking up
of rocks.
Hydraulic Action
Water is thrown into cracks within the cliff
by breaking waves. Air inside the cracks is
squashed by the water and the pressure
inside increases
When the wave sinks back, the pressurised
air expands explosively. This causes the
rocks to shatter so the cracks slowly
become bigger and deeper.
Weathering
Wetting/drying
Constant wetting and drying causes rocks to
expand and contract, resulting in surface
cracks and weakening of the rock.
Freeze thaw Weathering
Water gets into cracks in rocks and expands
as it freezes, putting pressure on the
surrounding rock.
Corrosion
Carbon Dioxide dissolves in rainwater,
producing acid rain. This reacts with
minerals inside certain rocks (e.g.
limestone), causing them to be weakened
and easily dissolved.
Erosion on Hard Coastlines
How are headlands and bays formed?
1) Hard (e.g. chalk)
and soft rock (e.g.
boulder clay) are
at right angles to
the coastline.
4) As the headland
juts out to sea, it
receives the full
force of the waves
energy. This allows
the headland to be
eroded slowly over
time.
2) Soft rock is eroded
at a faster rate by
hydraulic action and
abrasion.
3) Over time, a bay is formed within the soft rock. The shape of the coastline reduces the
energy forming constructive waves. This allows beaches to form.
How are cave, arches and stacks formed?
Headland
4) Overtime, the
base of the stack is
eroded by abrasion
which then topples
over in a storm to
form a stump.
1) A cave is formed
when hydraulic
action widens the
joints in the rock
over time.
2) An arch is formed
when hydraulic action
and abrasion continue to
erode the backwall of a
cave all the way through
the headland.
3)A stack is formed when the roof of
the arch is weathered by freeze thaw
action. This weakens it causing to
collapse as a rock fall due to gravity.
How are wave cut notches and platforms formed?
2) The top of the cliff is
weakened by freeze
thaw weathering.
1) Erosion from the
sea (i.e. abrasion
and hydraulic
action) start to
undercut the cliff
base.
.
4) Cliff collapses due to gravity
as a rockfall.
5) The cliff slowly retreats back
leaving a wave cut platform
behind.
3) This wave cut notch increases in size until the weight of the cliff
can no longer be supported.
Erosion on Hard Coastlines
How do rockfalls happen?
Process:
Freeze thaw weathering is when water
enters cracks between rocks and freezes.
This causes the water to expand which
puts pressure on the surrounding rocks.
Over time, it weakens the rock causing it
to break up. This causes rock to fall from
the cliff face due to gravity as a rockfall.
Landforms
A scree slope of fallen rock is formed at
the bottom of the cliff face.
Erosion on Soft Coastlines
SLUMPING
Process:
Slumping is a rapid movement of boulder clay that
occurs on a curved slip plane.
It happens when water percolates (soaks into) into
the boulder clay until it becomes saturated with
water making it heavy. The weight of the cliff above
it forces the rock down towards the sea as a mud
flow.
Landforms:
A step like cliff face is present after the slumping has
occurred. Vegetation (originally from the cliff top)
will also be present in patches on the cliff face.
LANDSLIDES AND MUDFLOWS
Process:
A landslide is a rapid movement of boulder clay that
occurs on a slip plane that is parallel to the cliff face.
It happens when erosion from the sea undercuts the
base of the cliff. This destabilises the cliff face
causing the clay to slide down the cliff as a
landslide.
Landforms:
An accumulation of sediment remains at the base of
the cliff which is known as a scree slope.
Deposition: How are beaches formed?
Swash Aligned Beach
Waves approach the
coastline and then break in
parallel to the coastline
Swash and backwash
move sediment up and
down the beach.
Creates an even profile
along the shoreline
During storms, berms
(ridges of sediment can
form).
Drift Aligned Beaches (longshore drift)
3)Backwash moves the
material straight back
down the beach to the
sea.
2) Swash
moves the
material up
the beach at
an angle.
1) Prevailing wind
direction moves waves
onshore at an angle.
4) Material is picked up
again and moved back up
the beach as swash.
6)The sediment
moves in a zig-zag
motion along the
beach. Over time,
large amounts of
sediment are
moved along the
beach.
5) Backwash brings the
material back down the
beach again.
Deposition: How are spits and bars formed?
e.g. Spurn Head,
Holderness Coastline
e.g. Slapton Ley,
Devon
How is a spit formed?
How is a bar formed?
1. Waves carrying material are blown in the
direction of the prevailing wind.
1. Waves carrying material are blown in the
direction of the prevailing wind.
2. Longshore drift moves material along the
coast.
2. Longshore drift moves material along the
coast.
3. Where the coastline changes direction,
material is deposited in water sheltered by
the headland.
3. Where the coastline changes direction,
material is deposited in water sheltered by
the headland.
4. The material builds upwards and outwards
to form a spit.
4. The material builds upwards and outwards
to form a spit.
5. A mud flat starts to develop in the
sheltered water behind the spit due to less
erosion.
5. The spit continues to grow across the bay
area and joins to the headland to form a
bar.
6. Secondary winds can cause the end of the
spit to curve forming a hooked end
6. A lagoon is formed behind the bar. Over
time, this is filled up with sediment to form
land.
7. The salt marsh develops on the mud flat in
the sheltered water.
Coastal Management
Why do some areas of the coast need protecting but not others?
There are 4 Management Options for
each section of coastline:
Do nothing (let the coast erode
naturally)
Hold the line (defend the coastline to
keep the coastline where it is at present)
Advance the Line (build defences
further out from the existing coastline to
help reclaim lost land)
Managed realignment (develop
defences further inland and permit some
coastal flooding)
Not all coastlines can be protected as this would be
highly expensive.
There a variety of socio-economic reasons why seaside
towns need to be protected. This includes where large
numbers of people live and local businesses.(e.g.
Bridlington).The Easington Gas Terminal also needs
protecting because it is so important in providing gas
for the UK whilst also providing jobs.
The whole of the Holderness coast is vulnerable to
erosion as it is made of soft rock. This means decisions
are made about which bits to hold the line and which
areas will have to be allowed to erode back.
Shoreline Management Plan
The aim of the Shoreline Management Plan is to identify which areas of coast require protection,
and which don’t. By looking at the coast as a whole, planners can make sure that any changes to
one part of the coast will not impact another part of the coastline.
Pevensey Bay: An example of Soft Engineering
Definition: Working with the natural processes of sea and sand in a more environmentally
sustainable way. Using the natural processes to bring about an intended effect.
Name & Picture
How does it reduce
erosion?
Advantages
Disadvantages
Beach Recycling
As sediment moves due to
longshore drift, some parts of the
beach lose sediment whilst others
gain sediment. To even this out,
material is moved back to the
areas where sediment has been
lost. This is carried out after
winter storms.
•
Beach
Replenishment
Dredgers are used to take sand
from the sea bed which is then
sprayed onto the beach. This
replaces lost beach material from
longshore drift and produces a
large beach. This causes more
friction and reduces erosion.
Adds to tourist
amenity by
making bigger
beach
• Attractive – no
unsightly
structures like
hard engineering
• Works with the
natural
processes of the
coast therefore
more
environmentally
friendly
Beach Reprofiling
This involves using bulldozers to
push sediment up the beach. This
changes the slope angle of beach
from steep to gentle. This allows
for more wave energy to be
absorbed reducing erosion.
Sometimes plants are placed at
the back of the beach to soak up
wave energy.
•
Needs frequent
renewal of more
sand
• Does not
protect cliff
face against the
energetic and
destructive
winter storm
waves.
• Local people
have the opinion
that soft
engineering is
not as good as
hard
engineering.
Holderness Coast: An example of Hard Engineering
Definition: Controlled disruption of natural processes (e.g. erosion and longshore drift)
by using man-made structures.
Name & Picture
How does it
reduce erosion?
Advantage
Disadvantages
Sea Wall (e.g.
Hornsea)
Curved sea walls
reflect the energy of
the waves back to the
sea preventing erosion
of the cliff.
Protects the base of
cliffs, land and
buildings against
erosion. Can prevent
coastal flooding in
some areas.
Can be expensive to
maintain as sea-walls
are eroded over time.
Rock Armour (e.g
Hornsea)
Absorb wave energy
reducing the erosion
of the cliff face.
Cheaper than sea
walls.
Unsitely and reduces
access to beach. Can
be expensive to obtain
and transport the
boulders.
Gabion (e.g.
Hornsea)
Absorb wave energy
reducing the erosion
of the cliff face.
Easily installed and
cheaper than sea walls.
Not very attractive,
needs frequent
checking & repair, not
easy for people to get
over to get to beach,
may contain rats nests
Groyne (e.g.
Hornsea)
Reduces the rate of
longshore drift
allowing a large beach
to develop. The
because causes
friction with waves
reducing wave energy
thus causing less
erosion
Allows a large beach
to form encouraging
tourism.
Can be seen as
unattractive. Costly to
build and maintain
Cliff Drainage
(Mappleton)
Pipes and drains are
put into the cliff to
remove water that
causes slumping.
Can be used on soft
rocks effectively.
Can cause erosion
where water leaves
the pipe into the sea.
Can affect local
wildlife
Tetrapods (Japan)
Absorb wave energy
reducing the erosion
of the cliff face.
Can be built on site.
Reduces transport
costs.
Isn’t completed
effecting at reducing
erosion as some wave
energy is not
absorbed.
How can we protect the coast from sea level rise? Managed realignment
Case Study: Wallasea Island, Essex
What is managed realignment?
Managed realignment involves the construction of new sea wall at a location behind
existing sea wall. This allows the area between the old and new sea wall to become
flooded forming a saltmarsh. The created saltmarsh helps reduce erosion and protects
against sea-level rise.
Case Study of managed realignment: Wallasea Wetlands, Essex, UK
What has happened?
With the coastal defences in the north of
the island crumbling away, the
government decided to realign (change
the shape of) the northern part of the
island by constructing a new
embankment (wall) inland (further south)
and allow the sea to further break
through (breach) the old sea defences.
How has it worked?
The formed salt marsh provides a
natural defence against flood tides and
will be increasingly important as sea
levels rise. Sea water is able to spread
out over the salt marsh reducing the risk
of flooding further inland. Reduced
erosion will also take place as plants
absorb wave energy.
Has it been successful?
Benefits:
Farmland wasn’t lost in the creation of the
salt marsh.
Few buildings were destroyed.
Fisheries were improved
Created 115 ha of saltmarsh for birds.
 It meant that they saved money that would have
otherwise been uselessly spent on replacing the current
sea defenses i.e. a new sea wall that would have cost
around £1,000,000 per kilometre..
Case Study: How can we make the Holderness Coastline sustainable?
What are the current pressures along the Holderness coastline?
• Farming related pollution
• Overfishing
• Footpath erosion
• Alternative sources of energy
• Overpopulation
• Tourism
What is the ICZM and what are the aims?
• ICZM stands for Integrated Coastal Zone
Management. It is a 100 page document
informing planners on how to be sustainable along
the coastline.
• Aims to reduce the pressures along the
Holderness Coastline by encouraging sustainable
practices.
Sustainability: Meeting the needs of the people
today without causing problems for future peoples.
How is the ICZM along the Holderness Coast sustainable?
ICZM
Element
To encourage
appropriate
offshore wind /
wave power
generation
To support
schemes that have
environmentally
friendly farming
techniques
To ensure the
continued
viability of the
inshore fishing
industry
To provide on-site
information and
education
materials to
educate and
inform both
visitors and local
people.
Environmental
sustainability
Social
Sustainability
Economic
Sustainability
Reduces amount of fossil
fuels burnt which release
greenhouse gases. This will
help reduce the threat of
global warming.
Reduces energy prices as less
money has to be paid on
importing fossil fuels. It makes
energy affordable for low
income people.
Provides jobs during the
manufacture and maintenance
of offshore wind and wave
energy plants.
Farmers use less chemicals
such as fertilizer and
pesticides which cause
water pollution. This helps
keeps coastal waters clean.
Food grown organically has a
higher nutritional value due to
higher vitamin and mineral
content. People become
healthier.
Environmentally friendly
techniques cost less to
implement so farmers see
larger profits which can help
compensate loss of land
through erosion.
Fish stocks remain high for
all species allowing for
biodiversity and
maintenance of existing
food webs.
Provides people with a
sustainable supply of different
varieties of fish at low prices.
Provides a balanced diet.
Provides fishermen with long
term job security as fish stocks
are being sustained.
Prevents footpath erosion
and trampling of plants. Bird
species do not get disturbed
by visiting tourists
Local visitors centre to
educate people about the
wildlife at various coastal
locations and how to protect it
Profits made through tourism
can be used to further
conservation work in coastal
areas.